Wall board



Patented Sept. 6, 1932 UNITED STATES PATENT OFFICE- LESLIE S. ODELL, F MONTREAL, QUEBEC, CANADA, ASSIGNOR T0 BUILDING PRODUCTS LIMITED, 015 MONTREAL, QUEBEC, CANADA WALL BOARD Application filed April 15,

This invention relates to new and useful improvements in wall board and particularly to insulating board used for inside walls, partitions and the like and the main object of he invention is to provide an insulating board to which plaster may be quickly and easily applied without saturating the board.

Another object is to provide an insulating board having moisture proof material in proximity to the side to which plaster is applied.

According to my invention, I provide an insulating board built up of a plurality of layers of fibrous material said layers being cemented together by any of the well known cementitious compounds used for this purpose. To this board I apply an outer layer which is attached to the aforementioned by a waterproofing compound. The said outer layer is of fibrous material and may be treated to render same moisture proof.

To illustrate my invention, I have shown a cross sectional elevation of a board built according to my invention.

Referring more particularly to the drawing, 11, 12, 13 and 14 designate separate layers of fibrous material or pulp which are held together by an adhesive compound 15 to form a comparatively thick insulating .board. "It it well known that if plaster is applied to the surface of the board in this state it would become a pulpy mass and would swell. Owing to the uneven drying of the plaster and the board, it will be readily seen that internal stresses would be set up in the board and also in the plaster which possibly would result in cracking of the plaster. It is also well known when the plaster is applied directly to the board that moisture is absorbed by the board even after the plaster has set, resulting in bad marking of the plaster. To overcome the above difliculties, is the main object of this invention and to attain this object, I apply an outside layer 17 which is secured to the aforementioned layers by a cementitious waterproofing material 18 such as asphalt. This layer of waterproofing compound between the two outer layers 14 and 17 of the board allows plaster tobe placed on to the surface 19 without affecting v 1929. Serial No. 355,220.

the layers 11, 12, 13 and 14 as the moisture from the wet plaster will not penetrate the layer 18 and affect the board. It will also be seen that the layer 18 prevents moisture which may be absorbed by the layers 11 to14 inclusive from affecting the plaster once same has set. For illustrative purposes I have shown the layer 18 to be of asphalt, but it will be readily understood that the layer 18 may consist of an asphalt treated layer of fibrous material, the asphalt being used as an adhesive to form a bond between the adjacent surfaces of the layers 17 and 14.

In use, plaster is readily applied to the surface 19 without affecting the back layer of the board as the layer 18 acts as a barrier for the passage of the moisture through the board.

Having thus described my invention, what I claim is:

A wall board construction comprising a plurality of separate layers of fibrous material adhesively united in face to face relation to form a comparatively thick insulating board, each layer comprising a mass of fibrous material which is continuous throughout the length and width of the layer and a plaster receiving surface for said board comprising an additional layer of fibrous material joined to an outer layer of said board by a comparatively thin layer of asphaltio waterproof material adapted to serve as a barrier against the penetration of moisture from said additional layer.

In witness whereof, I have hereunto set my hand.

LESLIE S. ODELL. 

